In current disk grinding apparati, a cylindrical surface included for grinding is rolled over a grinding disk that is controlled by a cam plate. However, due to the grinding disk resting with its edge on the cylindrical surface, the formation of ridges on the surface to be processed cannot be avoided. In fact, in a worst case situation, turning of the surface may be required, followed by equalizing and finish grinding which, in most cases, involves several time consuming working steps. In addition, the turning and subsequent grinding operations contribute to the wear of the cylinder, thus reducing the overall life of the cylinder to be processed. These subsequent operations are particularly difficult and expensive at the ends of the cylinder which have slightly convex edges and require special devices to achieve acceptable results.
It is further necessary to preheat the turning and grinding machines over long periods of time since the machines are not protected against the radiating heat of the heat cylinder.
An apparatus of this type is known from DE-OS 36 39 264. Here, between two brackets mounted on columns, a support and an adjustable profile plate acting as a guideway and having a form corresponding to the set value of the spherical surface accuracy are provided. On the profile plate and the support, a grinding belt device that includes a grinding belt drive, a feed slide with adjusting devices and axially displaceable guide bushings and a clamping device are located.
A disadvantage which generally prevails in the grinding of worn uneven cylindrical surfaces is that, after an initial grinding phase, the cylindrical surface has both machined and unmachined spaces that have different radiating conditions. The machined surfaces give off less heat than the unmachined surfaces so that different temperatures are present in the cylinder wall. This results in uneven thermal expansions on the surface to be ground which, in turn, leads to inaccurate grinding of the cylinder surface.